Fast 90 Intake porting..
Joined: Jul 2005
Posts: 531
Likes: 1
From: Texas, Europe, Iraq & Afghanistan
02402RAMAIR: In a couple pictures it looks like the top of the FAST 90 port is larger than the head's intake port. Any thoughts about adding plastic to the FAST 90 or taking some away from the head for a nice smooth transition?
The ports are exactly the same. I think what you are looking at is the witness mark. I filled the bottom witness mark in while I was blending in the bottom of the intake to intake port. I left the top witness mark intact. the pictures don't do justice. I can run my fingers through the ports and I have no lips, bumps or edges. I hope all the extra effort pays off.
above the witness mark is a pocket for the injector. that may be what you are looking at. I did nothing to that area because it does not mate to the head.
should this area be reworked.
I have serched for pictures to give me direction but could not find any.
anyone have pictures?
should this area be reworked.
I have serched for pictures to give me direction but could not find any.
anyone have pictures?
I ended up JB welding my upper corners and radiusing the upper centers. DOn't know if thats better or worse, but my ports match up nice. I recently bought a plastic welder fro Harbor Frieght. I now wonder if that would have been better to use to fill in the upper corners.
Joined: Jul 2005
Posts: 531
Likes: 1
From: Texas, Europe, Iraq & Afghanistan
Thanks! I'm looking for an extra 25HP and 25LBTQ in my combination. I think the porting can get me another ten or so. I may then look for a larger 95mm throttle body and MAF. If I don't make it then I'll add cubic inches and go for fifty more.
Yes, I'm glad you said the ports are flush. Then the pictures are indeed deceiving. It sounds like the FAST ports are fairly close to the head's intake ports.
I added a picture (your picture cropped) and highlighted in yellow the area were the FAST port looks larger than the head's intake port.
Were the gaskets/o-rings very expensive?
Again, thanks!
Yes, I'm glad you said the ports are flush. Then the pictures are indeed deceiving. It sounds like the FAST ports are fairly close to the head's intake ports.
I added a picture (your picture cropped) and highlighted in yellow the area were the FAST port looks larger than the head's intake port.
Were the gaskets/o-rings very expensive?
Again, thanks!
The ports are exactly the same. I think what you are looking at is the witness mark. I filled the bottom witness mark in while I was blending in the bottom of the intake to intake port. I left the top witness mark intact. the pictures don't do justice. I can run my fingers through the ports and I have no lips, bumps or edges. I hope all the extra effort pays off.
Last edited by Gregory; Oct 11, 2008 at 11:03 PM.
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Verdad Gallardo Joined: Jul 2005
Posts: 531
Likes: 1
From: Texas, Europe, Iraq & Afghanistan
ROCNDAV: How much filler did you need to add in thousands? .050, .100, or more?
Were you able to dyno after the work and measure a difference?
Thanks!
Were you able to dyno after the work and measure a difference?
Thanks!
I ended up JB welding my upper corners and radiusing the upper centers. DOn't know if thats better or worse, but my ports match up nice. I recently bought a plastic welder fro Harbor Frieght. I now wonder if that would have been better to use to fill in the upper corners.
02402RAMAIR, great write up and pics my friend. i home ported mine like you and i managed to gain 35rwhp/10rwtq OVER the Ls6 intake I had on my car!!! this is with Patriot Stage II Ls6 style heads (59cc), and a little Comp 224. numbers in my sig...
I roughed up the corners of the intake then built up the area with the JBweld (couldnt tell you off hand how much, just enough that the intake port was now smaller than the head port).
I purchased some 6mm threaded rod and made some stud like fixtures to torque the intake down and used an air grinder to make ports flush.
I haven't dyno'd anything, so I cant tell you if I helped or hurt anything.
above the witness mark is a pocket for the injector. that may be what you are looking at. I did nothing to that area because it does not mate to the head.
should this area be reworked.
I have serched for pictures to give me direction but could not find any.
anyone have pictures?
should this area be reworked.
I have serched for pictures to give me direction but could not find any.
anyone have pictures?
Thanks! I'm looking for an extra 25HP and 25LBTQ in my combination. I think the porting can get me another ten or so. I may then look for a larger 95mm throttle body and MAF. If I don't make it then I'll add cubic inches and go for fifty more.
Yes, I'm glad you said the ports are flush. Then the pictures are indeed deceiving. It sounds like the FAST ports are fairly close to the head's intake ports.
I added a picture (your picture cropped) and highlighted in yellow the area were the FAST port looks larger than the head's intake port.
Were the gaskets/o-rings very expensive?
Again, thanks!
Yes, I'm glad you said the ports are flush. Then the pictures are indeed deceiving. It sounds like the FAST ports are fairly close to the head's intake ports.
I added a picture (your picture cropped) and highlighted in yellow the area were the FAST port looks larger than the head's intake port.
Were the gaskets/o-rings very expensive?
Again, thanks!
that area is open for the injector. (pic below)
I don't know if it would help to fill this area or not.
ANYONE know what to do to this area?
Last Saturday I pulled my FAST to check for a possible vacuum leak. While I had it all disassembled, I decided to match port the bottom shell to the stock LS1 heads, and open up the runners a little.
This is the unported FAST bottom sitting on the stock LS1 heads - notice the heads showing up on the right and slightly at the bottom.
I stuffed rags down the intake runners, and match ported the heads to the intake using a die grinder with carbide bit and sandpaper rolls:
I also opened up the center piece a little
As I re-assembled the intake, I went ahead and added a set of 30# SVO injectors to replace my stockers:
My stock combination was not tested, but I will have the current setup dyno tuned next week. So unfortunately I can't add any concrete data to this discussion, just sharing how I spent my Saturday afternoon.
This is the unported FAST bottom sitting on the stock LS1 heads - notice the heads showing up on the right and slightly at the bottom.
I stuffed rags down the intake runners, and match ported the heads to the intake using a die grinder with carbide bit and sandpaper rolls:
I also opened up the center piece a little
As I re-assembled the intake, I went ahead and added a set of 30# SVO injectors to replace my stockers:
My stock combination was not tested, but I will have the current setup dyno tuned next week. So unfortunately I can't add any concrete data to this discussion, just sharing how I spent my Saturday afternoon.
Joined: Apr 2004
Posts: 1,378
Likes: 14
From: Atlanta, GA Ft. Walton Beach, FL
Fast Last Saturday I pulled my FAST to check for a possible vacuum leak. While I had it all disassembled, I decided to match port the bottom shell to the stock LS1 heads, and open up the runners a little.
This is the unported FAST bottom sitting on the stock LS1 heads - notice the heads showing up on the right and slightly at the bottom.
I stuffed rags down the intake runners, and match ported the heads to the intake using a die grinder with carbide bit and sandpaper rolls:
I also opened up the center piece a little
As I re-assembled the intake, I went ahead and added a set of 30# SVO injectors to replace my stockers:
My stock combination was not tested, but I will have the current setup dyno tuned next week. So unfortunately I can't add any concrete data to this discussion, just sharing how I spent my Saturday afternoon.
This is the unported FAST bottom sitting on the stock LS1 heads - notice the heads showing up on the right and slightly at the bottom.
I stuffed rags down the intake runners, and match ported the heads to the intake using a die grinder with carbide bit and sandpaper rolls:
I also opened up the center piece a little
As I re-assembled the intake, I went ahead and added a set of 30# SVO injectors to replace my stockers:
My stock combination was not tested, but I will have the current setup dyno tuned next week. So unfortunately I can't add any concrete data to this discussion, just sharing how I spent my Saturday afternoon.
the hole on the intake is to big, I would be mad at Comp. for poor quaility control.
I think the car will run much better now that you smoothed it.
where are you having it dynoed an tuned Trussville?
My intake is a 78mm. I bought it used for roughly the same price as an LS6 intake. I haven't been able to run it hard since re-assembling it because with the 30# injectors and no tuning it goes to 9:1 AFR at WOT. Yes, I plan on a trip to Trussville next week. I would have run down today, but decided spending V-day with my wife was a better decision in the long term...
